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                                                                    Exhibit 31.1
                                  CERTIFICATION

I, Leonard Osser, certify that:

     1.  I have reviewed this annual report on Form 10-KSB of Milestone
         Scientific Inc. ("the registrant").

     2.  Based on my knowledge, this annual report does not contain any untrue
         statement of a material fact or omit to state a material fact necessary
         to make the statements made, in light of the circumstances under which
         such statements were made, not misleading with respect to the period
         covered by this annual report;

     3.  Based on my knowledge, the financial statements, and other financial
         information included in this annual report, fairly present in all
         material respects the financial condition, results of operations and
         cash flows of the registrant as of, and for, the periods presented in
         this annual report;

     4.  The registrant`s other certifying officer and I are responsible for
         establishing and maintaining disclosure controls and procedures (as
         defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the
         registrant and have:

         a)   Designed such disclosure controls and procedures to ensure that
              material information relating to the registrant, including its
              consolidated subsidiaries, is made known to us by others within
              those entities, particularly during the period in which this
              annual report is being prepared;

         b)   Evaluated the effectiveness of the registrant's disclosure
              controls and procedures as of a date within 90 days prior to the
              filing date of this annual report (the "Evaluation Date"); and

         c)   Presented in this annual report our conclusions about the
              effectiveness of the disclosure controls and procedures based on
              our evaluation as of the Evaluation Date; and

     5)  The registrant's other certifying officer and I have disclosed, based
         on our most recent evaluation, to the registrant's auditors and the
         audit committee of registrant's board of directors (or persons
         performing the equivalent functions):

         a)   All significant deficiencies and material weaknesses in the design
              or operation of internal controls which are reasonably likely to
              adversely affect the registrant's ability to record, process,
              summarize and report financial information; and

         b)   Any fraud, whether or not material, that involves management or
              other employees who have a significant role in the registrant's
              internal controls; and

     6.  The registrant's other certifying officer and I have indicated in this
         annual report whether or not there were significant changes in internal
         controls or in other factors that could significantly affect internal
         controls subsequent to the date of our most recent evaluation,
         including any corrective actions with regard to significant
         deficiencies and material weaknesses.

Date: March 31, 2006
                                    /s/ Leonard Osser
                                    -----------------
                                    Leonard Osser
                                    Chairman and Chief Executive Officer